This paper delves into the theoretical mechanisms of the electronic structure and optical properties of aluminum-based semiconductors(AlX,X=N,P,As,Sb)and indium-based semiconductors(InX,X=N,P,As,Sb)as potential materi...This paper delves into the theoretical mechanisms of the electronic structure and optical properties of aluminum-based semiconductors(AlX,X=N,P,As,Sb)and indium-based semiconductors(InX,X=N,P,As,Sb)as potential materials for optical devices.Band structure calculations reveal that,except for InSb,all other compounds are direct bandgap semiconductors,with AlN exhibiting a bandgap of 3.245 eV.The valence band maximum of these eight compounds primarily stems from the p-orbitals of Al/In and X.In contrast,the conduction band minimum is influenced by all orbitals,with a predominant contribution from the p-orbitals.The static dielectric constant increased with the expansion of the unit cell volume.Compared to AlX and InX with larger X atoms,AlN and InN showed broader absorption spectra in the near-ultraviolet region and higher photoelectric conductance.Regarding mechanical properties,AlN and InN displayed greater shear and bulk modulus than the other compounds.Moreover,among these eight crystal types,a higher modulus was associated with a lower light loss function value,indicating that AlN and InN have superior transmission efficiency and a wider spectral range in optoelectronic material applications.展开更多
Transition metal dichalcogenides are interesting candidates as photocatalysts for hydrogen evolution reaction.The MnPSe_(3)/WS_(2) heterostructure is hence studied here with first principles calculations by exploring ...Transition metal dichalcogenides are interesting candidates as photocatalysts for hydrogen evolution reaction.The MnPSe_(3)/WS_(2) heterostructure is hence studied here with first principles calculations by exploring its electronic properties under the application of an electric field.It is discovered that the band gap will decrease from the WS_(2) monolayer to the MnPSe_(3)/WS_(2) heterostructure with Perdew-Burke-Ernzerhof functional,while increase slightly when electron correlation is involved.The conduction band minimum of the heterostructure is determined by the MnPSe3 layer,while the valence band maximum is contributed by the WS_(2)layer.The band edges and band gap suggest that the heterostructure will have good photocatalytic properties for water splitting.Moreover,comparing to monolayer WS_(2),the light absorption in both the ultraviolet and visible regions will be enhanced.When an electric field is present,a linear relation is observed between the electric field and the band gap within specific range,which can thus modulate the photocatalytic performance of this heterostructure.展开更多
The electronic structure and optical properties of VO2 and Au-VO2 were studied using density functional theory. The calculation results show that the interaction between Au and O is stronger than that between V and O....The electronic structure and optical properties of VO2 and Au-VO2 were studied using density functional theory. The calculation results show that the interaction between Au and O is stronger than that between V and O. There exists not only the covalent bonding but also ionic bonding in Au--O bond. The band gap of Au-VO2 is smaller than that of VO〉 while the dielectric constant, conductivity, and intensity of optical absorption of Au-VO2 are larger than those of VO2.展开更多
Using the first-principles calculations based on density functional theory(DFT),the structure stability,electronic and some optical properties of C and N doped cubic ZrO2(c-ZrO2) in 24-atom systems were investigated.I...Using the first-principles calculations based on density functional theory(DFT),the structure stability,electronic and some optical properties of C and N doped cubic ZrO2(c-ZrO2) in 24-atom systems were investigated.It is found from the formation energies calculations that N ions are easier to be doped into c-ZrO2 than C ions.The electronic structure results show that Zr8O15C and Zr8O15N systems are semiconductors with the band gap of 2.3 eV and 2.8 eV,respectively,which are lower than that of the pure ZrO2(3.349 eV).And optical properties results depict that anion doping,especially C adding,can enhance the static dielectric function,visible and ultraviolet light absorption and reflecting ability of c-ZrO2 crystal.展开更多
The equilibrium lattice parameters, electronic structure, bulk modulus, Debye temperature, heat capacity and Gibbs energy of TiB and TiB2 were investigated using the pseudopotential plane-wave method based on density ...The equilibrium lattice parameters, electronic structure, bulk modulus, Debye temperature, heat capacity and Gibbs energy of TiB and TiB2 were investigated using the pseudopotential plane-wave method based on density functional theory (DFT) and the improved quasi-harmonic Debye method. The results show that the total density of states (DOS) of TiB2 is mainly provided by the orbit hybridization of Ti-3d and B-2p states, and the total DOS of TiB is mainly provided by the hybrids bond of Ti-3d and B-2p below the Fermi level and Ti—Ti bond up to the Fermi level. The Ti—B hybrid bond in TiB2 is stronger than that in TiB. Finally, the enthalpy of formation at 0 K, heat capacity and Gibbs free energy of formation at various temperatures were determined. The calculated results are in excellent agreement with the available experimental data.展开更多
文摘This paper delves into the theoretical mechanisms of the electronic structure and optical properties of aluminum-based semiconductors(AlX,X=N,P,As,Sb)and indium-based semiconductors(InX,X=N,P,As,Sb)as potential materials for optical devices.Band structure calculations reveal that,except for InSb,all other compounds are direct bandgap semiconductors,with AlN exhibiting a bandgap of 3.245 eV.The valence band maximum of these eight compounds primarily stems from the p-orbitals of Al/In and X.In contrast,the conduction band minimum is influenced by all orbitals,with a predominant contribution from the p-orbitals.The static dielectric constant increased with the expansion of the unit cell volume.Compared to AlX and InX with larger X atoms,AlN and InN showed broader absorption spectra in the near-ultraviolet region and higher photoelectric conductance.Regarding mechanical properties,AlN and InN displayed greater shear and bulk modulus than the other compounds.Moreover,among these eight crystal types,a higher modulus was associated with a lower light loss function value,indicating that AlN and InN have superior transmission efficiency and a wider spectral range in optoelectronic material applications.
基金Project(2682019CX06)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(2019KY23)supported by Research Start-up Fund from the Southwest Jiaotong University,China+2 种基金Projects(20ZDYF0236,20ZDYF0490)supported by the Key R&D Projects in the Field of High and new Technology of Sichuan,ChinaProject(52072311)supported by the National Natural Science Foundation of ChinaProject(2019JDJQ0009)supported by the Outstanding Young Scientific and Technical Talents in Sichuan Province,China。
文摘Transition metal dichalcogenides are interesting candidates as photocatalysts for hydrogen evolution reaction.The MnPSe_(3)/WS_(2) heterostructure is hence studied here with first principles calculations by exploring its electronic properties under the application of an electric field.It is discovered that the band gap will decrease from the WS_(2) monolayer to the MnPSe_(3)/WS_(2) heterostructure with Perdew-Burke-Ernzerhof functional,while increase slightly when electron correlation is involved.The conduction band minimum of the heterostructure is determined by the MnPSe3 layer,while the valence band maximum is contributed by the WS_(2)layer.The band edges and band gap suggest that the heterostructure will have good photocatalytic properties for water splitting.Moreover,comparing to monolayer WS_(2),the light absorption in both the ultraviolet and visible regions will be enhanced.When an electric field is present,a linear relation is observed between the electric field and the band gap within specific range,which can thus modulate the photocatalytic performance of this heterostructure.
基金Project(2014GXNSFAA118342)supported by Guangxi Natural Science Foundation,ChinaProject supported by Open Foundation of Guangxi Key Laboratory for Advanced Materials and Manufacturing Technology,ChinaProject supported by High-level Innovation Team and Outstanding Scholar Program in Guangxi Colleges(the second batch),China
文摘The electronic structure and optical properties of VO2 and Au-VO2 were studied using density functional theory. The calculation results show that the interaction between Au and O is stronger than that between V and O. There exists not only the covalent bonding but also ionic bonding in Au--O bond. The band gap of Au-VO2 is smaller than that of VO〉 while the dielectric constant, conductivity, and intensity of optical absorption of Au-VO2 are larger than those of VO2.
基金Project(61172047) supported by the National Natural Science Foundation of China
文摘Using the first-principles calculations based on density functional theory(DFT),the structure stability,electronic and some optical properties of C and N doped cubic ZrO2(c-ZrO2) in 24-atom systems were investigated.It is found from the formation energies calculations that N ions are easier to be doped into c-ZrO2 than C ions.The electronic structure results show that Zr8O15C and Zr8O15N systems are semiconductors with the band gap of 2.3 eV and 2.8 eV,respectively,which are lower than that of the pure ZrO2(3.349 eV).And optical properties results depict that anion doping,especially C adding,can enhance the static dielectric function,visible and ultraviolet light absorption and reflecting ability of c-ZrO2 crystal.
基金Project(07JJ3102)supported by the Natural Science Foundation of Hunan Province,ChinaProject(k0902132-11)supported by the Changsha Municipal Science and Technology,China
文摘The equilibrium lattice parameters, electronic structure, bulk modulus, Debye temperature, heat capacity and Gibbs energy of TiB and TiB2 were investigated using the pseudopotential plane-wave method based on density functional theory (DFT) and the improved quasi-harmonic Debye method. The results show that the total density of states (DOS) of TiB2 is mainly provided by the orbit hybridization of Ti-3d and B-2p states, and the total DOS of TiB is mainly provided by the hybrids bond of Ti-3d and B-2p below the Fermi level and Ti—Ti bond up to the Fermi level. The Ti—B hybrid bond in TiB2 is stronger than that in TiB. Finally, the enthalpy of formation at 0 K, heat capacity and Gibbs free energy of formation at various temperatures were determined. The calculated results are in excellent agreement with the available experimental data.
